OIL OIL LAB TESTING What does it all mean??

Note: I used QS Defy in my Cherokee (the 4.0 is a flat-tappet engine)...Blackstone Labs analysed a sample, and with 180,000+ miles, it was the best UOA they had EVER gotten from a Jeep 4.0! Yes, I'm sold on Defy!

In summer, I run 15W-40 diesel oil (currently Rotella), which also has extra ZDDP.